Door closers are commonly used to control the movement of a door between open and closed positions. One common complaint concerning door closers used in the past is that they either permit the door to move too rapidly to the closed position, often shutting with a slam, or they impose too much resistance to closing and hence unduly retard and slow the movement of the door to fully closed position.
It is a primary object of this invention to provide a door closing piston-cylinder assembly which overcomes these objections. The door closing assembly of this invention permits the door to be opened with relative ease, and then on closing movement, the door is allowed initially to move to closed position fairly rapidly but with controlled restraint until it approaches the fully closed position whereupon the door continues to move but considerably more slowly so that it will close smoothly and softly and without a bang. Just before the door reaches fully closed position the restraint on door movement is substantially relieved to allow the door to assume a fully closed and latched position.
Another object of the invention is to provide a door closing assembly which is composed of a relatively few simple parts, is capable of being inexpensively manufactured, is rugged and dependable, and is well-suited for the accomplishment of its intended function.
These and other objects, features and advantages of the invention will become more apparent as the following description proceeds, especially when considered with the accompanying drawings.